Conventionally, there has been known a remote system in which a receiving device and a transmitting device are connected to each other via a Cat 5 (Category 5) cable, i.e., a LAN (Local Area Network) cable (See Japanese Laid-Open Patent Publication No. 2004-356939). In the remote system, the transmitting device transmits a video signal (an analog RGB signal) to the receiving device with three pairs of signal lines in the Cat 5 cable. In addition, the transmitting device transmits and receives a console signal such as a keyboard/mouse signal to/from the receiving device with a remaining pair of signal lines.
A remote system in which the single Cat 5 cable to be connected between the transmitting device and the receiving device is extended is required. In the required remote system, a DVI (Digital Visual Interface) signal and various control signals are transmitted from the transmitting device to the receiving device.
However, since the DVI signal is composed of four pairs of differential signals, all signal lines in the Cat 5 cable (i.e., four pairs of signal lines) are occupied by the DVI signal, and cannot transmit a control signal. Therefore, two Cat 5 cables are connected between the transmitting device and the receiving device, and the DVI signal and the control signal are transmitted via the different signal lines, respectively.